The test verifies identical shapes and verifies values with
abs(desired-actual)<0.5*10**(-decimal).

Given two array_like objects, check that the shape is equal and all
elements of these objects are almost equal. An exception is raised at
shape mismatch or conflicting values. In contrast to the standard usage
in numpy, NaNs are compared like numbers, no assertion is raised if
both objects have NaNs in the same positions.